Recording process



United States Patent "ice 3,385,700 RECORDING PROCESS Jozef FransWillems and Albert Lucien Poot, Wilrijk-Antwerp, Belgium, assiguors toGevaert Photo-Producteu,

Mortsel, Belgium, a Belgian company i No Drawing. Filed June 10, 1965,Ser. No. 463,029 Claims priority, application Great Britain, June 12,1964,

24,520/ 64 11 Claims. (Cl. 96-27) The present invention relates to aprocess for recording optical information by means of a materialcontaining a cyclohexadienone compound.

We have found that a light-sensitive system based on thephototransformation of a cyclohexadienone compound into a compound,which is reactive with a nucleophilic reagent, can be used for recordingand reproducing optical information.

It is an object of the present invention to provide a photographicprocess using a recording medium containing a cyclohexadienone compound.

It is a further object of the present invention to provide aphotographic material having a water-permeable layer containing a3,5-cyclohexadienone compound having in orthoposition to the oxo groupat least one acetoxy group or a 2,5-cyclohexadienone compound having inpara-position to the 0x0 group at least one acetoxy group preferably acompound according to the following general formulae respectively:

wherein R represents an acetoxy group,

R represents hydrogen, or a hydrocarbon group e.g. alkyl or aryl, anether group or an acetoxy group,

each of R R R and R represents hydrogen, or a hydrocarbon group e.g.alkyl such as methyl, ethyl, n-propyl, isopropyl, n-butyl, tert. butyl,or isoamyl, an aryl group or substituted aryl group, acetyl or allyl,

whereby R and R together may represent the atoms necessary to close anaromatic ring,

R and R, as well as R, and R together may represent the atoms necessaryto close a homocyclic saturated ring, and

each of R',, R ,R R' and R' represents hydrogen, alkyl or aryl, and

R represents an acetoxy group.

Compounds according to the first general formula, which are particularlysuited for use according to the present invention, have the followingstructural formulae:

3,385,700 Patented May 28, 1968 A compound according to the secondgeneral formula, which is particularly suited for use according to thepresent invention is represented by the following structural formula:

The compounds formed on exposing the above-mentioned cyclohexadienonecompounds are ketene intermediates.

According to a first type of recording and reproduction method a visibleimage can be produced in a photographic element containing one of saidcyclohexadienone compounds, by image-wise or record-wiseU.V.-irradiating said element thereby transforming said cyclohexadienonecompound into a ketene compound, which is reactive with a nucleophilicreagent, and by allowing said ketene compound to react with saidnucleophilic reagent to produce a condensation product, which can bedetected by means of a colour reaction, thereby forming a colouredproduct on the exposed areas.

According to a particular photographic reproduction method fallingwithin the scope of this first type, the ketene compound formed byexposure is allowed to react in the photographic element with water,resulting in the image-wise formation of a diene acid. The image-wiseformed acid can now be used to produce a visible image e.g. by detectingthe acid with suitable pH-indicators, which undergo a colour changeunder the influence of the hydrogen atoms.

According to a modified method of the said first type of photographicreproduction, the image-wise formed acid can be used to neutralise abaseimage-wise, whereby the non-neutralised base on the unexposed areas cane.g. be detected by means of a pH-indicator.

According to another modified method of the said first type ofphotographic reproduction it is possible to produce an image-wisebleach-out reaction by using in the photographic element the saidcyclohexadienone compound together with a base and a colouredpH-indicator, which at a lower pH-value is transformed into a colourlesscompound.

Classes of pH-indicators, the representatives of which are suited forbeing applied in the present invention, are e.g. nitrophenols, azocompounds, phthaleins and sulphophthaleins.

Further it should be remarked that the image-wise pH- difierentiationobtained according to one of the types of the foregoing photographicreproduction methods can in principle be used to produce image-Wise apH-dependent colour reaction or to form substances building up an imageby using the catalysing influence of the image-wise produced hydrogenions or image-wise neutralised hydroxyl ions.

According to a second type of recording and reproduction method, avisible image can be produced in a photographic element containing oneof said cyclohexadienone compounds by image-wise or record-wiseU.V.-irradiating said element thereby transforming said cyclohexadienonecompound into a ketene compound, which on the exposed areas blocks thechemical reactivity of a reactant, which is incorporated in the saidelement before or after exposure, and after exposure allowing theresidual reactant to react at the unexposed areas with a reaction agentto form a coloured product.

According to a particular photographic reproduction method fallingwithin the scope of the second-mentioned type of reproduction method,the ketene compound formed on exposing a cyclohexadienone compound isallowed to react with a colour coupler possessing a reactive functionwith respect to a-coupler coupling agent which may be incorporated inthe same material. The colour coupler is chosen such that the reactiveradical thereof is blocked by reaction with the ketene compound formedon exposure and is thus excluded from any reaction with a colourcoupling agent on the exposed parts. By treating now the exposedmaterial with a suitable colour coupling agent, image-diiferentiation isobtained.

Suitable colour couplers are colour couplers having a coupling functionof the nucleophilic type e.g. colour couplers containing reactivehydrogen atoms in the coupling position, such as the colour-formingcompounds containing a reactive methylene or phenolic hydroxyl groupcapable of reacting with the oxidation products of primary aromaticamino coupling developers. Particularly suitable colour couplers arethose of the phenol or naphthol type.

The cyclohexadienone compounds used in the process of the presentinvention can be prepared according to known techniques. As anillustration thereof references of the preparation are givenhereinafter.

Monatsh. Chemie:

The cyclohexadienone compounds used in the present invention are mainlyU.V.-sensitive. The rate of phototransformation is relatively thehighest in the wavelength range of 300 m,u-432 me.

A photographic material for copying purposes according to one of theabove-described recording and reproduction methods can be prepared bycoating a cyclohexadienone compound from a solution or dispersion onto-a support, which may be more or less porous, e.g. a paper support orcan be prepared by incorporating a cyclohexadienone compound into aliquid-permeable layer, preferably a water-permeable layer in order toallow the diffusion therein of chemical reactants. For preparingwaterpermeable layers, preferably binding agents are used, which areonly slightly or almost not Water-soluble at room temperature but whichform water-permeable layers when coated from a solution in an organicsolvent e.g. ethanol. Suitable binding agents are e.g. ester gums, whichare freed from resinous and waxy substances, and cellulose derivativesforming water-permeable layers such as ethylcellulose and collodion.

Preferably the cyclohexadienone compound is incorporated innon-migratory form into a liquid-permeable layer or support.

Known colour couplers used in multilayer systems in principle are madenon-migratory by joining long chain groups to their molecules. Inprinciple this is also possible for the cyclohexadienone compounds (andcolour reactants if any) incorporated in photographic material forcarrying out the present invention.

It is therefore possible in principle to produce multicolour images inaccordance with the present invention in a multilayer material whereine.g. in a first layer a yellow image, in a second layer a magenta imageand in a third layer a cyan image can be formed by applying in saidlayers a yellow, magenta and cyan colour coupler respectively andcarrying out a reproduction process of the second type referred toabove.

The following examples illustrate the present invention.

Example 1 A mixture of the following composition:

8 cm. of a 3% solution in ethanol of ester gum freed from resin and wax1 cm. of a 9% solution of 2-acetoxy-2-methyl-3,5-cyclohexadiene-l-one inacetone 1 cm. of a 0.4% solution of p-nitrophenol in acetone is appliedto a baryta-coated paper support in such a way that 1 g. ofcyclohexadienone compound is present per sq. m.

The dried layer is treated with a solution of 0.4 g. of sodium hydroxideand 1 g. of lauryl sulphate as wetting agent in a mixture of 90 cm. ofethanol and 10 cm. of water. After having been dried to the air, thephotographic material has a yellow colour.

The photographic material is exposed for 2 min. through ablack-and-white diapositive of a line original with the aid of a Philipsultra-violet-radiating bulb of watts placed at a distance of 10 cm.

At the exposed areas the material has turned from yellow to colourless.

Example 2 A mixture of the following composition:

8 cm. of a 3% solution of the ester gum of Example 1 in ethanol 1 cm. ofa 9% solution of the cyclohexadienone compound of Example 1 in acetone 1cm. of a 0.4% solution in ethanol of Alizarin Yellow R having thefollowing structure:

OONa

is applied to a baryta-coated paper support in such a way that 1 g. ofcyclohexadienone compound is present per sq. m.

The dried layer having a red colour is exposed as described in Example1.

At the exposed parts the red colour has turned to yellow.

Example 3 A mixture of the following composition:

8 cm. of a 3% solution of the ester gum of Example 1 in ethanol 1 cm. ofa 9% solution of the cyclohexadienone compound of Example 1 in acetone 1cm. of a 0.4% solution in ethanol of phenolphthalein is coated on abartya-coated paper support in such a way that 1 g. of cyclohexadienoneis present per sq. m.

The dried layer is treated with an alkaline solution as described inExample 1.

During exposure as described in Example 1, the exposed parts turned fromred to colourless. In this way a positive image is obtained.

Example 4 A mixture of the following composition:

8 cm. of a 3% solution of the ester gum of Example 1 in ethanol 1 cm. ofa 9% solution of the cyclohexadienone compound of Example 1 in acetone 1cm. of a 0.4% solution of Bromothymol Blue (dibromothymolsulphophtalein, sodium salt) in ethanol is applied to a baryta-coatedpaper support in such a way that 1 g. of cyclohexadienone is present persq. m.

The dried layer is exposed as described in Example 1.

At the exposed areas the colour turned from blue to yellow.

Very good results are also obtained by substituting Cresol Red (o-cresolsulphophthalein, sodium salt), Chlorophenol Red, or Bromocresol Purple(dibromoo-cresol sulphophthalein, sodium salt) for Bromothymol Blue.

Example 5 A mixture of the following composition:

8 cm. of a 3% solution of the ester gum of Example 1 in ethanol 1 cm. ofa 9% solution of the cyclohexadienone compound of Example 1 in acetone 1cm. of a 0.4% solution of eosin (sodium salt) in ethanol is applied to abaryta-coated paper support in such a way that 1 g. of cyclohexadienoneis present per sq. m.

The dried layer is exposed as described in Example 1 but for 5 min.

At the exposed areas the colour turned from red to pink.

Example 6 A mixture of the following composition:

8 cm. of 3% solution of ester gum (freed from resin and wax) in ethanol1 cm. of a 9% solution of the cyclohexadienone compound of Example 1 inacetone 1 cm. of a 0.1% aqueous solution of the oxonol compound havingthe following structure:

is applied to a baryta-coated paper support in such a way that 1 g. ofcyclohexadienone compound is present per sq. in.

After having been dried to the air, the layer is exposed as described inExample 1.

The colour of the exposed areas turned from colourless to blue.

Example 7 A mixture of the following composition:

8 cm. of 3% solution of ester gum (freed from resin and wax) in ethanolcm. of a 9% solution of the cyclohexadienone compound of Example 1 inacetone cm. of a 4% aqueous solution of sodium hydroxide containing 0.4%of the oxonol compound having the following structure:

COOH

N N 0=o HO-( l p1 nae-hi3=oH-orr=orrorr=orr-o-o-om is applied to abaryta-coated paper support in such a way that 1 g. of cyclohexadienonecompound is present per sq. m.

After having been dried to the air, the layer is exposed as described inExample 1.

At the exposed areas the colour has turned from colourless to blue.

By treating then the material with an 0.1 N aqueous solution of hydrogenchloride, the blue image areas hecome reddish brown.

Example 8 If in the foregoing example the mentioned oxonol compound isreplaced by one havin the following structure:

on on 2 cm. of a 0.2% solution in dimethylformamide of a compound havingthe following structure:

CH: O s neonll (IE-011:0

is applied to a baryta-coated paper support in such a way that 1 g. of acyclohexadienone compound is present per sq. m.

The material dried to the air is exposed as described in Example 1. Apositive purple image is obtained.

Example 10' A mixture of the following composition:

9 cm. of a 3% ethanolic solution of the ester gurn of Example 1 1 cm. ofa 9% solution of the cyclohexadienone compound of Example 1 in acetone 2cm. of a 0.2% solution in dimethylformamide of is applied to abaryta-coated paper support in such a way that 1 g. of acyclohexadienone compound is present per sq. m.

The material dried to the air is exposed as described in Example 1, butfor 1 min. only. A green positive image is formed. A visually detectableimage-differentiation is already present after an exposure time of 5seconds.

7 Example 11 A mixture of the following composition:

8 cm. of a 3% ethanolic solution of the ester gum of Example 1 1 cm. ofa 9% solution of a cyclohexadienone compound of Example 1 in acetone 1cm. of a 0.4% solution in ethanol of4,4-bis-dimethylamino-3"-chlorotriphenylcarbonol is applied to abaryta-coated paper support in such a way that l g. of cyclohexadienonecompound is present per sq.m.

On drying to the air the material obtains a greenish tone.

By exposure to U.V.-light the exposed parts are bleached. The greenishtone, however, re-appears by contact of the material with atmosphericoxygen. By treating the exposed material for 30 sec. in a 0.05 Nhydrogen chloride solution and rinsing with water for 2 min., theunexposed image areas are bleached, while on the exposed areas a verystable green colour is obtained. Surprisingly an alkaline treatmentgives the same result.

An image of the same quality is obtained with the4,4'-bis-dimethylaminotriphenylcarbinol.

Example 12 A mixture of the following composition:

7 cm? if a 3% ethanolic solution of the ester gum of Example 1 1 cm. ofa 9% solution of the cyclohexadienone compound of Example 1 in acetone 2cm. of a 1% ethanolic solution of a-naphthol Example 13 A mixture of thefollowing composition:

7 cm. of a 3% ethanolic solution of the ester gum of Example 1 1 cm. ofa 9% solution of the cyclohexadienone compound of Example 1 in acetone 2cm. of a 2% aqueous solution of a colour coupler having the followingstructure:

CONE-O l SOaNa SOaNa 1 cm. of a 2.5% solution ofdiethyl-p-phenylenediamine hydrochloride,

is applied to a baryta-coated paper in such a way that 1 g. ofcyclohexadienone compound is present per sq. m.

The dried layer is exposed as described in Example 1, except that theexposure time is only 1 min. The exposed material is developed in asolution of potassium hexacyanofer-rate'(III) in water/ethanol .(80/20).A greenish positive image is obtained.

8 Example 14 A mixture of the following composition:

7 cm. of a 3% ethanolic solution of the ester gum of Example 1 1 cm. ofa 9% solution of the cyclohexadienone compound of Example 1 in acetone 2cm. of a 2% aqueous solution of the colour coupler of Example 13 Example15 A mixture of the following composition:

7 cm. of a 3% ethanolic solution of the ester gum of Example 1 1 cm. ofa 30% solution of the cyclohexadienone compound of Example 1 in acetone2 cm. of a 2% ethanolic solution of the colour coupler having thefollowing structural formula:

S OsNB,

1 cm. of a 2.5% aqueous solution of diethyl-p-phenylene diaminehydrochloride is applied to a baryta-coated paper in such a way that 1g. of the cyclohexadienone compound is present per sq. m. The driedlayer is exposed as described in Example 1, and developed by treatmentwith a 10% alkaline solution (pH=9) of potassium hexacyanoferrate (III)A positive cyan image is obtained.

Example 16 A mixture of the following composition:

20 cm. of a 4% aqueous solution of poly(vinyl alcohol) 2.5 cm. of a 20%solution of the cyclohexadienone compound of Example 1 in acetone 2.5cm. of a 8% solution of 8-hydroxy quinoline in ethanol is applied to abaryta-coated paper in such a way that 1 g. of the cyclohexadienonecompound is present per sq. m.

The dried layer is exposed as described in Example 1 and developed bydipping in a 5% aqueous iron(III) chloride solution. First a positiveimage is obtained. By rinsing with water and drying to the air the imageis reversed:

Example 17 A mixture of the following composition:

20 cm. of a 4% aqueous solution of poly(vinyl alcohol) 2.5 cm. of a 20%solution of the cyclohexadienone compound of Example 1 in acetone 2.5cm. of a 8% solution of hydroquinone in ethanol is applied to abaryta-coated paper in such a way that 1 g. of the cyclohexadienonecompound is present per sq. m.

The dried layer is exposed as described in Example 1. The exposedmaterial is developed with an ammoniacal silver nitrate solution.Immediately after the contact with said solution, a positive image isformed, which, however, disappears very rapidly in favour of a reversalimage.

With gallic acid and pyrogallol similar results are obtained as withhydroquinone.

Example 18 A mixture of the following composition:

3 cm. of a 2% solution of 4,4'-bis-dirnethy1amino-3"-chlorotriphenylcarbinol in acetone.

2 cm? of a 9% solution of 2,2-diacetoxy-4-methyl-3,5-

cyclohexadiene-l one in acetone Example 19 A mixture of the followingcomposition:

7 cm. of a 15% ethanolic solution of the ester gum of Example 1 3 cm. ofa 10% solution of 2-acetoxy-2-methyl-3,S-cyclohexadiene-1one in acetone3 cm. of a 1% solution of a-naphthol in acetone is applied to abaryta-coated paper support.

After having been dried to the air, the layer is exposed as described inExample 1 and treated with an alkaline coupling solution as described inExample 12.

A stable positive brown image is obtained. The background has a palebrown colour.

Example 20 A mixture of the following composition:

7 cm. of a solution of ethylcellulose in acetone 2 cm. of a 10% solutionof the cyclohexadienone compound described in Example 18 in acetone 1cm. of a 2% aqueous solution of a colour coupler as described in Example13 is applied to baryta-coated paper support.

The dried layer is exposed and developed as described in Example 13.

A greenish positive image is obtained.

Example 21 A mixture of the following composition:

2 cm. of a 10% solution of 4-acetoxy-4-methyl-2,5-

cyclohexadiene-l-one in acetone 3 cm. of a 2% solution of a carbinolbase as described in Example 18 in acetone is applied to a baryta-coatedpaper support.

On drying to the air the material obtains a greenish tone.

The exposure and development is carried out as described in Example 18.

At the exposed areas a very stable green colour is obtained.

Example 22 A mixture of the following composition:

7 cm. of a 5% solution of ethylcellulose in acetone 2 cm. of a 7.5%solution of the cyclohexadienone compound having the followingstructural formula:

1 cm. of a 2% aqueous solution of the colour coupler as described inExample 13 is applied to a baryta-coated paper support.

The dried layer is exposed and developed as described in Example 13.

A greenish positive image is obtained.

From the foregoing it will be seen that the invention permits positivecopies to be obtained directly from positive original documents, or fromnegative originals, according to the ingredients of the recordingmaterial.

While reference has been made to processes in which the image isproduced in the recording material, which is image-wise or record-wiseexposed to the radiation, this is not essential since the selectivetransformation of the cyclohexadienone compound to ketene in onematerial can be made to form a visible image in another material, whichmay itself embody the nucleophilic agent or such agent and apH-indicator or colour coupler, e.g. by bringing the two materialstogether in face to face contact while wet, either during or after theexposure step, and then peeling the materials apart.

The invention is, of course, not only applicable to the making of imagesof readable matter but can be applied for recording any selectiveexposure pattern such as optical signals.

We claim:

1. A photographic process comprising the step of image-wise orrecord-wise exposing to U.V.-radiation an element containing asU.V.-sensitive compound a 3,5- cyclohexadienone compound containing inortho-position to the oxo group at least one acetoxy group or a 2,5-cyclohexadienone compound containing a para-position to the oxo group atleast one acetoxy group.

2. A photographic process according to claim 1, wherein the element alsocontains a nucleophilic reagent capable of reacting with a compoundformed by exposing the said cyclohexadienone compound to U.V.-radiati0n.

3. A photographic process according to claim 1, wherein said elementcontains a cyclohexadienone compound corresponding to one of thefollowing general formulae:

wherein:

R represents an acetoxy group,

R represents a member selected from the group consisting of hydrogen, ahydrocarbon group, an ether group and an acetoxy group,

each of R R R and R represents a member selected from the groupconsisting of hydrogen and a hydrocarbon group,

each of R' R R' R' and R' represents a member selected from the groupconsisting of hydrogen, an alkyl and an aryl group,

R' represents an acetoxy group, and wherein R and R may represent theatoms necessary to close an aromatic ring, and

R and R as well as R, and R together may represent the atoms necessaryto close a homocyclic saturated ring.

4. A photographic process according to claim 1, com prising the furtherstep of detecting by colour reaction the reaction product formed byreaction between a nucleophilic reagent and the compound formed onexposing to U.V.-radiation said cyclohexadienone compound.

5. A photographic process according to claim 2, wherein the nucleophilicreagent is reagent is reacted in situ with the compound formed byinteraction of actinic light on the cyclohexadienone compound, and theunreacted nucleophilic reagent is reacted with another compound toproduce a product absorbing visible light.

6. A photographic process according to claim 2, wherein the nucleophilicreagent is water and the detection of the reaction product is carriedout by means of a pH-indicator.

7. A photographic process according to claim 2, wherein the nucleophilicreagent is a colour coupler having a reactive hydrogen atom in thecoupling position.

8. A photographic process according to claim 2, wherein the nucleophilicreagent is a colour coupler having a reactive methylene or phenolichydroxyl group capable of reacting with the oxidation products of aprimary aromatic amino coupling developer.

9. A photographic process according to claim 2, wherein the nucleophilicreagent is a carbinol base.

10. A photographic process according to claim 2, wherein thenucleophilic reagent is a phenolic hydroxyl groupcontaining photographicdeveloper and the exposed material is developed by means of anammoniacal silver nitrate solution.

11. A recording material comprising a layer, that incorporates a3,5-cyclohexadienone compound containing in ortho-position to the oxogroup at least one acetoxy group or a 2,5-cyclohexadienone compoundcontaining in para-position to the OX0 group at least one acetoxy groupand that also incorporates a nucleophilic agent in the form of a colourcoupler with groups that can react directly or indirectly with a keteneformed by exposure of the cyclohexadienone compound to ultra-violetradiation and thereby cease to be available for reaction with a colourcoupling agent.

No references cited.

NORMAN G. TORCHIN, Primary Examiner.

J. E. EVERETT, Assistant Examiner.

1. A PHOTOGRAPHIC PROCESS COMPRISING THE STEP OF IMAGE-WISE ORRECORD-WISE EXPOSING TO U.V.-RADIATION AN ELEMENT CONTAINING ASU.V.-SENSITIVE COMPOUND A 3,5CYCLOHEXADIENONE COMPOUND CONTAINING INORTHO-POSITION TO THE OXO GROUP AT LEAST ONE ACETOXY GROUP OR A2,5CYCLOHEXADIENONE COMPOUND CONTAINING A PARA-POSITION TO THE OXO-GROUPAT LEAST ONE ACETOXY GROUP.
 2. A PHOTOGRAPHIC PROCESS ACCORDING TO CLAIM1, WHEREIN THE ELEMENT ALSO CONTAINS A NUCLEOPHILLIC REAGENT CAPABLE OFREACTING WIITH A COMPOUND FORMED BY EXPOSING THE SAID CYCLOHEXADIENONECOMPOUND TO U.V.-RADIATION.